
Scenario 1 -
In a Central Administration Server - Managed Backup Exec Server ( CAS -MBES ) environment CAS is upgraded first. It could happen that the agents on the remote server being backed up in that environment are upgraded and Managed Backup Exec Server ( MBES ) is missed and remains on older Backup Exec version. In such a case if the Backup job is delegated to run from MBES and backs up a remote server which has the agent updated to higher version then the job fails with above mentioned error.
Scenario 2 -
Backup Exec Server is running a lower version than the agent which is installed on remote server to back it up.
Update the Backup Exec Server ( Managed or Standalone ) to the version matching the agent installed on remote server or vice versa.
V-79-57344-3841 - The version of the Agent for Windows is incompatible with the version of Backup Exec server attempting to access it